Cars blamed for drop in air quality

Dangerous chemicals that aggravate asthma and can damage lungs are rising in Australian cities as more cars hit the road, a national report on air quality has found.

While four key air pollutants dropped between 1991 and 2001, the increase in tiny airborne particles - mostly from motor vehicles - is a concern for those who suffer respiratory illnesses.

The particle matter is measured in two sizes, PM10 and PM2.5. PM10 has been linked to increased respiratory problems, aggravation of asthma, more hospital admissions and premature death. The elderly, children and asthma or heart disease sufferers are at most risk.

The finer particles of PM2.5 can penetrate deep into the respiratory system and have been connected to increased hospital admissions for heart and lung diseases and premature death.

The particles can also come from domestic wood heaters, bushfires, wind-blown dust, sea salt and industrial facilities such as power stations.

The other chemical on the rise is ground-level ozone, the principal chemical in photochemical smog. It is formed when sunlight and other chemicals - from cars, refineries, petrochemicals and vegetation - react. It, too, can have adverse effects on the respiratory system, asthma and lung function.

The report found that Launceston, with its smoke from wood heaters collecting in a valley, has levels of PM10 far above the national standard.

Sydney, with its particular air circulation patterns, has excessive levels of PM2.5.

Melbourne was below the national standard for both air pollutants. However, the report warned that levels were rising.

Releasing the State of the Air report yesterday, federal Environment Minister David Kemp said: "The challenge we've got in this area is that while we are actually making our fuel cleaner and our vehicles are emitting less pollutants, people are using more vehicles and travelling more. So it is a constant effort to make sure that we continue to reduce the pollutants in the atmosphere."

National and state regulations have resulted in marked declines in four key pollutants: carbon monoxide, nitrogen dioxide, sulphur dioxide and lead. The successful measures have included the banning of lead petrol, national controls on car emissions and advances in industrial and vehicle technology.

Dr Kemp said that the reliance on fossil fuels will wane, but in the meantime more stringent pollution controls were needed to reduce harmful chemicals.

"The issue is going to be how quickly can we introduce the hydrogen fuel cell vehicle," he said. And that's not going to come tomorrow. We're going to see these vehicles on the road over the next decade, but it's going to be some time before we move into the post-fossil-fuel economy.

"And that's why we need to keep making our standards more stringent in relation to fossil fuels and vehicle emissions."

Meanwhile, a meeting yesterday of state and federal environment ministers decided to set up a national monitoring system for another five air toxics - benzene, polycyclic aromatic hydrocarbons, formaldehyde, toluene and xylenes. These toxics have been linked to a range of health problems, including asthma, respiratory illnesses and cancer.

The ministers also committed funds to research the impact of city air pollution on children and have adopted, in principle, a plan to recycle television sets, although they want more detail from industry on how a take-back scheme will work.

The ministers also welcomed recycling schemes from the tyre and computer industries.